Appliance for shearing metal.



C. R. MONTGOMERY.

APPLIANCE FOR SHEARING METAL.

APPLICATION FILED SEPT. 2I. 1914.

3,22%@ PfIIenIed June 5,1917.

I #II-lll IIIIIIIIIIW n mmm CHARLES ROBERT MONTGOMERY, OF KEYNSHAM, NEARBRISTOL, ENGLAND.

APPLIANCE FOR SHEARING METAL.

Specification of Letters Patent.

Patented June 5, 1917..

Appli-cation filed September 21, 1914. Serial No'. 862,851.'

T 0 all er1/0m il? may concern.'

Be it known that l, CHARLns ROBERT MONTGOMERY, a subject of the King ofGreat Britain and Ireland, residing at Keynsham, near Bristol, in thecounty of Somerset, England, have invented certain nen7 and usefulmprovements in Appliances for Shear-ing Metal; and I do hereby declarethe following' to be a. full, clear and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

This invention relates to a metal shearing appliance or tool moreespecially intended for shearing corrugated sheets and has for itsobject to provide a portable device for hand use, whereby the shearingof such sheets may be accomplished in an eiiicient manner and withoutdistortion of the cut edges and in which the operation of the toolsimultaneously and automatically effects the feed or relative movementbetween the tool and the sheet.

To this end the invention comprises a pair of rotary shearing members(hereinafter referred to as the cutters) mounted upon a frame or member,one of which cutters is adapted to be driven while the other runs free,said cutters being formed with duplicate and parallel cutting edges, theperiphery of the driven cutter being knurledor otherwise formed withteeth-like serrations, the whole operating in such manner that a stripof the sheet being operated upon is cut out and deflected to enable thetool to automatically travel in the gap or opening so obtained.

The feed strip above referred to may be gripped between the periphery ofthe driven cutter, or a circumferential portion thereof, and a bearingsurface formed on the other cutter between the cutting edges, and foradjusting this grip or pressure upon said strip, suitable means areprovided said means also serving for the purpose of releasing thecutters by moving them apart to enable the tool to be removed in thecase where it is required to only partly cut across a sheet.

In Order to adapt the tool to cut curves the frame or member upon whichthe cutters are mounted is suitably backed off or reduced in thicknesstoward the rear or trailing edge of said frame.

The driven cutter is preferably driven by means of a ratchet device of.any suitable type operated by a handle adapted to be reciprocated by theuser the tool being supported meanwhile and guided by another handlerigidly secured to the frame, said handles being held one in each hand.

In some cases the bearing surface between the cutting edges of the freecutter may be in the form of a separate ring loosely mounted thereon,knurled or not, to facilitate the relative or feeding movement betweensheet and cutters.

The accompanying drawings illustrate by way of example one form of theimproved tool in which Figure l is a side elevation.

Fig. 2 is a front elevation partly in section on the line F-Fof Fig. las seen looking in the direction of the arrow m1.

Fig. 3 is a rear viewy looking in the direction of the arrow y1. Fromthis figure both handles and certain other parts are omitted in order toshow clearly the configuration of the frame and the guides or cheeksrelatively to one another.

Fig. 4 is a detail plan partly in section on the line GHG of Fig. lshowing the method of attachment of the holding or guide handle.

Referring to the drawings. 88 is the driven cutting member which ismilled or knurled around both butting edges and between these edgesadditional milled surface is provided as at 39, of the same diameter' asthe cutting edges, serving the purpose of a driven feed roller. Betweenthe cutting edges of the free running cutter 40 is a milled bearingroller, 4l of smaller diameter than the said cutting edges. rlhe roller4l is free to rotate about its aXis. The driven cutting member 38 ismounted in cheeks 42 at one end of the frame 43, toward the opposite endof which are mounted the cheeks 44 carrying the free cutting member 40and the free bearing roller 41. From the frame 43 extends the handle 45by which the tool is held in position and guided. The handle 45 is heldto the frame 43 by the pin 46 which projects into the cheeks 42 as seenmore particularly in Fig. 4. Shoulders 47 are formed on the handle 45 totake the forward thrust of the cheeks 42 in the process of cutting. Thecheeks are held from moving in the opposite direction by the pin 46which passes into recesses 48 formed in the cheeks 42, said recessesbeing elongated to allow for adjustment of the cheeks 42,

In order to allow for different gages of metal the cheeks 42 are mountedeither on bearings, or in any other convenient manner, thus I mayprovide an adjustment block 49 which is adjustable by means of a nut 50and screw 51 so that the cutting member 38 can be adjusted toward oraway from the cutting member 40. The block 49 is held up to theadjusting nut 50 by means of a spring 52. Such provision for adjustmentmay if desired be made in respect of the free cutter 40 instead of thedriven cutter 38.

The driven cutter 38 engages, by clutch or other means, with ratchets 53which are driven by pawls 54 acted upon by springs 55 carried on aratchet handle 56 which is pivotally mounted on the spindle 58, and heldthereon by means of flanged collars 57 screwed on the spindle 58, andthis spindle passes through the center of and rotates with the drivencutter 38.

In order to permit the mounting of the free bearing roller 41, the freecutter 40 is made in two halves, which are secured together by means ofcollars 59 screwed on a spindle 60, as seen more particularly in Fig. 2.

In Fig. 1 a piece of corrugated sheet 61'is shown in the process ofbeing cut; and the feed strip 62 is seen after passing out between andbelow the cutting edges of the free cutter 40, thus leaving a clearnessor gap 63 (see Fig. 4) for the passage of the tool.

The diameter of the bearing roller 41 relative to the diameter of thecutting edges should be such that when the thickest gage of metal thatthe tool is adapted for, is being cut., the cutting edges of the upperand lower cutters should overlap as little as possible. rIhe capacityfor adjustment by means of the nut 50 should be such that the cutter 38may be capable of further separation from the cutter 40 to allow forwithdrawing the tool, and, in the opposite direction, to approach thecutter 40 until the feed roller 39 and the bearing roller 41 are incontact with one another.

In operation, the tool should be held firmly against the edge of thesheet, preferably the right hand edge, with the handle 45 pointing inthe direction of the cutting line; as the driven cutter 38 is rotated bythe ratchet handle 56 which is held by the right hand, the toolcommences to cut and traverse at the same time being guided by the lefthand. The feed strip 62 is delected downward by the upper cutter 38 andthereafter is forced to follow the contour of the inside edge of theframe 43 until it emerges below the lower cutter 40 as seen in Fig. 1.

In the operation of cutting, the natural inclination of the tool is suchthat a line joining the aXes of the two cutters 38 and 40,

such as the line F-F Fig. 1, is perpendicular to theplane of the sheetat the actual point of cutting: consequently when cutting at rightangles to the corrugations, the tool should be allowed to inclinebackward as it rides up the corrugations and forward as it rides downthe same. It follows when cutting at an angle to the corrugations, otherthan at a right angle, the tool will also require to lean alternatelyt-o'one side and the other in addition to being inclined forward andbackward as already described.

In order to allow for the varying inclinations of the tool, as abovedescribed, and to allow for the clearance for the back edge of the frame43 when cutting on a curve, the thickness of the center portion of theframe 43, as represented by the portion between the shade lines in Fig.1, is made approximately only half the width of the clearance 63- Fig.4-which is created by the diversion of the feed strip 62 as alreadydescribed. The f minimum radius of curve which the tool is capable ofcutting, is to a considerable eX tent dependent upon the amount ofclearance between the back of the frame 43 and the cut edges of thesheet 61 in the clearance 63 as explained above. In Fig. 4 the clearance63 is shown as cut on a curve and it will be seen that one corner of theframe 43 is abutting against the cut edges of the sheet. This portion ofthe frame 43 may be taperedat the back edges to allow more latitudewhere required.

Having thus described my invention, what I claim and desire to secure byLetters Patent of the United States is A 1. An appliance foi1 shearingcorrugated or other formed sheets comprising a frame, means for holdingsaid frame, a driven rotary cutter and a co-acting' free rotary cuttermounted on said frame, each of said cutters having a plurality ofparallel cutting edges spaced apart and said driven cutter beingprovided with a knurled or dentated portio-n between its cutting edgesadapted to be impressed into the metal beinU operated upon, meanswhereby the metal between the edges of said free cutter is supported,and means carried by the frame whereby the strip of metal so sheared isdeflected in advance of the frame to allow the free passage of the tool,substantially as described.

2. An appliance for shearing corrugated or other formed sheetscomprising a frame, means for holding said frame, a driven rotary cutterand a co-acting free rotary cutter mounted on said frame, each of saidcutters having two annular parallel cutting edges' spaced apart, andsaid driven cutter being provided with a knurled or dentated portionbetween its cutting edges adapted to be impressed into the metal beingoperated upon, the said free cutter being provided with knurled ordentated portions around its periphery, and means carried by the framewhereby the strip of metal so sheared is de 13e lected in advance of theframe to allow the free passage ot the tool, substantially as described.

3. An appliance for shearing corrugated or other formed sheetscomprising a traine, means for holding said frame, a driven rotarycutter and a co-acting free rotary cutter mounted on said frame, each otsaid cutters having a pair of annular' parallel cutting edges spacedapart, and said driven cutter being provided with a knurled or dentatedsurface between its cutting edges adapted to be impressed into the metalbeing operated upon, a freely mounted bearing ring disposed between theedges of said free cutter, and means carried by the frame whereby thestrip ot metal so sheared is deflected in advance ofthe frame to allowthe free passage of the tool, substantially as described.

4t. An appliance for shearing corrugated or other formed sheetscomprising a frame, means for holding' and guiding said frame, a drivenrotary cutter and a co-acting free rotary cutter mounted on said frame,each of said cutters having a pair of annular parallel cutting edgesspaced apart, and said driven cutter being provided with a knurled ordentated surface between the cutting edges adapted to be impressed intothe metal being operated upon, a pivoted handle, and means controlledthereby for intermittently rotating said driven cutter in one direction,means whereby the metal lying between the edges of said free cutter issupported, and means carried by the frame whereby the strip of metal sosheared is deflected in advance of the frame to allow free passage ofthe tool, substantially as described.

5. An appliance for shearing corrugated or other formed sheetscomprising a framel reduced in thickness toward the rear or trailingedge, means for holding said frame, a driven rotary cutter and aco-acting free rotary cutter mounted on said frame, each of said cuttershaving a pair of annular parallel cutting edges spaced apart, and saiddriven cutter being provided with a knurled or dentated portion betweenthe cutting edges adapted to be impressed into the metal being operatedupon, means whereby the metal lying between the cutting edges of saidfree cutter is supported, and means carried by the trame whereby thestrip of metal so sheared is deflected in advance of the Irame to allowthe free passage of the tool, substantially as described.

6. An appliance for shearing corrugated or other formed sheetscomprising a frame, means for holding said frame, a driven rotary cutterand a co-acting free rotary cutter mounted on said frame, each of saidcutters having a pair of annular parallel cutting edges spaced apart,and said driven cutter being provided with a knurled or dentated portionbetween the cutting edges adapted to be impressed into the metal beingoperated upon, means whereby the metal lying between the edges of saidfree cutter is supported, means carried by the frame whereby the stripof metal so sheared is deflected in advance of the frame to allow thefree passage of the tool, and means `for adjusting the cuttersrelatively to each other, substantially as described.

7. An appliance for shearing corrugated or other formed sheetscomprising a trame, means for holding said frame, a driven rotary cutterand a co-acting free rotary cutter mounted on said frame, each of saidcutters having a pair oi' annular parallel cutting edges, spaced apart,and said driven cutter being provided with a knurled or dentated portionbetween the cutting edges adapted to be impressed into the metal beingoperated upon, means whereby the metal lying between the edges of saidfree cutter is supported, means carried by the frame whereby the stripof metal so sheared is deflected in advance of the frame to allow thefree passage o the tool, and means for adjusting the cutters relativelyto cach other comprising a pair of cheeks in which said driven cutter isjournaled, means for guiding said cheeks, and screw for moving saidcheeks, substantially as described.

In testimony whereof, I afiiX my signature, in presence of twowitnesses.

CHARLES ROBERT MONTGOMERY.

Vitnesses:

E. M. SMITH, NICHOLAS lVA'r'rs.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents, Washington, D. G.

